Manchester United manager Louis van Gaal described his side's crucial clash against Wolfsburg as the biggest of his reign at the club so far.
United are second to the Bundesliga club by a point in Group B, and need a win at the Volkswagen Arena on Tuesday to ensure qualification.
Van Gaal, facing criticism for his team's struggles in front of goal, said it was United's biggest game since he took charge 18 months ago.
"The moment is always the most important thing in this question as we have to fight against Manchester City in the league, or against Liverpool, and for the fans they are very important," he said.
"But in this moment, I believe this is the most important match but only at this moment."
Van Gaal said it was vital for United to advance in the Champions League. If United fail to win and PSV claim three points in Eindhoven, the Premier League club will play in the Europa League.
"It's also very important for the club to continue in the Champions League and also for the players because they want to show their qualities at the highest podium," Van Gaal added.
"That’s also why it is very important."
